Sirin was truly impressed by Zatiel wits and capabilities. The problem with selling records with knowledge, it's the fact that they are easily duplicated making his value plummet since a great number of copies could be done and flood the market.
But with the alteration that Zatiel did to the book, that problem was handled.
"We will perform the examination and if everything goes well, we will put the book in the auction and endorse them with our name. But I was wondering whether you will be willing to directly sell the 'Book of resurrection' to the auction house, we will pay you greatly of course."
The Magus was very interested in the rituals of the book. The knowledge about resurrection magic in the kingdom is not small, but the one related to bringing back people who had died of old age was uncommon, and more so if it only needed the power of a Rank 4 life form to be able to use it.
